It is usual in modern coating systems, particularly painting systems, for example for the coating of motor vehicle body parts, to use coating agent devices (e.g. needle valves, bell cups, atomizers, etc.) comprising conventional, standardized threads to be attachable to each other. Although conventional, standardized threads are well suited for a variety of purposes, they exhibit a number of disadvantages when used in coating/painting systems, predominantly resulting from the particular constraints in coating/painting systems.
Thus, for example, hose ruptures or overspray in coating systems can lead to the coating agent (e.g. paint, single component paint, two- or multi-component paint, etc.) or other common agents used in coating systems (e.g. detergents, rinsing agents, solvents, etc.) contaminating and affecting the threads of the coating agent devices and particularly to inadvertent locking (jamming) of the affected coating agent devices. Also in the normal operation of a coating system, it is almost impossible to isolate any thread to be found in the paint system completely from coating agents or other thread-affecting agents. Insofar as the coupling point between the coating agent devices is contaminated, e.g., by paint, two-component paints are particularly dangerous, there is a danger that the coating agent devices can no longer be non-destructively released from one another. An efficient maintenance- and cleaning-friendly coupling concept is thus not given.
Furthermore, there exists in the case of coating agent devices and the usual speeds in coating systems of around 8,000-80,000 rpm the danger of an inadvertent releasing, e.g. of a bell cup rotated by a turbine. Parts releasing at a speed of between 8,000-80,000 rpm can cause massive damage to the coating system and to the component to be coated. The danger of releasing exists particularly in the case of extreme acceleration or braking e.g. by a robot or a turbine.
Moreover, the assembly and disassembly effort of normal coating agent devices is relatively great, which results from the fact that several turns are required for screwing on to form a loadable thread connection, e.g. in the case of a bell cup generally at least five turns relative to the bell cup shaft. Similarly in the case of valves which are generally screwed on using 3 to 6 turns. However, assembly and disassembly of coating agent devices is mandatory due to the need for cleaning and replacement due to wear. Contamination of particular coating agent devices, e.g. a bell cup thread, could e.g. lead to a mechanical imbalance, which is associated with a corresponding mechanical loading of the bearing unit and in extreme cases can lead to a failure of the bearing unit.
Moreover, conventional coating agent devices lack an inserting-/alignment aid which makes attachment difficult and which further increases the time required for assembly of a coating agent device.
There also exists in the case of coating agent devices, e.g. electrostatic atomizers, the danger of high voltage peaks.
Document EP 1 157 747 A2 discloses an example of a valve with a conventional threaded connection.
In the light of the above explanations it is clear to the persons skilled in the art on the basis of this disclosure that there is a requirement to solve or overcome the above described problems or disadvantages. The present disclosure relates to this requirement of the prior art and to other requirements which are revealed to persons skilled in the art on the basis of this disclosure.
The exemplary illustrations are not limited, however, to examples that remedy all the problems or disadvantages of the prior art mentioned above. The exemplary illustrations are also directed to the examples described below.
The objects arising from the aforementioned can be achieved substantially with the features of the independent claims.